[Numpy-discussion] metadata and metabehavior for arrays (for scipy.base or Numeric3)

Sébastien de Menten sdementen at hotmail.com
Wed Apr 6 08:52:05 CDT 2005


>>
>>Maybe this one could be implemented using record array with a record like 
>>(data, mask). However, it would be cumbersome to use. E.g.  
>>a.field("data")[:] = cos( a.field("data")[:] ) instead of a[:] = cos(a[:]) 
>>with the current MA module
>
>Assuming "data" is the name of a field in a record array "a", why not have 
>a.data to represent a view (or copy, depending on the convention adopted) 
>of a column in a or a.data.Cos to provide the cosines of the values in the 
>data column?
>
>"Cos" is used in place of "cos" to distinguish the method from the 
>function.  The former requires no parentheses.
>

Well, I think the whole point is to be able to use "without changes" any 
library that manipulate arrays with "augmented arrays": same code for all 
arrays independently of them being "naked" or "augmented".

The "without changes" and "any library" should be taken with a pinch of salt 
as operation that are accepted for any array will not necessarily mean 
something for some "augmented arrays".

On a side note, I rather prefer to keep mathematical notation instead of OO 
notation ( cos as function vs method )






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